The present invention relates to a fastening clip for upholstered cover elements, in particular motor vehicle trim elements. The fastening clip has a flat, disc-shaped retainer head extending perpendicularly to the clip axis, a central circular neck having a length corresponding to the thickness of the trim element, a thin, disc-shaped sealing collar disposed parallel to the retainer head and retention elements adjoining the latter and formed by at least two mutually opposite spring tongues or resilient arms which cooperate through detent shoulders with a locating hole in the body panel.
A fastening clip substantially of the kind introductorily described is already known from German patent DT-AS No. 1,243,536. In the case of this fastening clip, the retention elements consist of two mutually opposite spring tongues or resilient arms which are formed by slotting a taper pin, adjoining a cylindrical reduced diameter used as a detent, which pin is of larger diameter than the diameter of the locating hole in the body panel.
It has been discovered, where these fastening clips are concerned, that the clip, which is made of injection-moulded low-elasticity synthetic material, can be manufactured with adequate accuracy but that the tolerances on the locating holes in the body panel, as well as the quality of the edge finish in the holes, fluctuates widely so that the clip is alternately either too tight or too loose in the hole when assembled. If the clip fits too tightly in the hole, then it is virtually impossible to remove the trim element or the like for repair purposes, for example, while if the clip fits too loosely, because of the various vibrations which develop in a motor vehicle, the trim element may start to rattle.
Another fastening clip of the kind introductorily described is already known from German petty patent DT-Gbm No. 1,930,693. In the case of this clip, the detent elements are formed by two mutually opposite spring arms which cooperate through elbow-shaped shoulders with a locating hole in the body panel. Again, with this clip, the same difficulties are encountered, namely, that the quality of the fit of the clip depends very largely upon the tolerance of the locating holes in the body panel, as well as upon the quality of the finish of the hole edges.